.mobile-header{
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    box-sizing: border-box;
    padding: .5rem;
    background: var(--default-ui-bgColor);

    display:flex;
    flex-direction: row;
    flex-wrap: nowrap;
    justify-content: flex-start;
    align-content: stretch;
    align-items: center;
}

.mobile-header .header-nav-btn {
    display:flex;
    justify-content:center;
    align-items:center;
    fill: #fff;
    width: 30px;
    height: 30px;
    line-height: 30px;
}